Display device and method for manufacturing display device

ABSTRACT

According to one embodiment, a display device includes a first substrate including a first area, a second area, a third area and a fourth area from an end portion to an inner side in a planar view. An organic insulating film is present in the second area and the third area, and is not present in the fourth area. A conductive film is formed at least on the organic insulating film of the second area. A sealing material is present in the first area, the third area and the fourth area to attach the first substrate and a second substrate. A through portion is adjacent to an inner side of the fourth area and penetrates the first substrate, the second substrate and the sealing material.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2016-077492, filed Apr. 7, 2016, theentire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a display device and amethod for manufacturing a display device.

BACKGROUND

Recently, liquid crystal display panels have been used for wearabledevices, which are assumed to be worn by the user. Liquid crystaldisplay panels can display pictures, letters, drawings, figures, etc.Since the display content can be switched, liquid crystal display panelsare expected to be used in various ways as wearable devices. Normally, aliquid crystal display panel comprises a first substrate on which aplurality of pixel electrodes are arranged, a second substrate facingthe first substrate, and a liquid crystal layer interposed between thefirst substrate and the second substrate. The liquid crystal displaypanel further comprises an outer circumferential sealing material. Thesealing material integrates the substrates along the outercircumferential portions of the substrates and seals the liquid crystal.

The above wearable devices include a wrist watch type integrated with aclock mechanism having hands. This device requires a small throughportion which penetrates the liquid crystal display panel to allocatethe axes of rotation of the hands. To seal the liquid crystal betweenthe substrates, an inner sealing material having a ring shape should beprovided around the through portion.

A process for manufacturing the above wearable device includes a stepfor applying the outer sealing material and the inner sealing materialto the first substrate, attaching the second substrate to the firstsubstrate, and injecting a liquid crystal.

Thus, the manufacturing process requires a step for applying the innersealing material around the small through portion so as to have a ringshape. In this step, an appropriate amount of sealing material needs tobe applied to each part of the ring in a process of forming a circularpattern. When the second substrate is attached to the first substrate,the substrates are pressed. At this time, the line width of the innersealing material should not exceed a predetermined width. However, whenthe sealing material is applied in a ring shape, the sealing materialmay be redundant at the overlapping connected portion for connectingsurely the start portion of the material with the end portion of thematerial. In the conventional device, in many cases, the width of theinner sealing material extends outward beyond the scope of theassumption when the second substrate is attached to the first substrate.As a result, the width of a light-shielding film also has to beincreased to shield the sealing material from light, in other words,such that the sealing material is not seen from the outside. When theline width of the sealing material is increased, a part of the sealingmaterial is extended to a display area and disturbs display.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a planar view schematically showing a first substrate of adisplay device according to one embodiment.

FIG. 1B schematically shows partially the structure of thecross-sectional surface of the display device according to theembodiment.

FIG. 2 includes a planar view showing the vicinity of the centralportion of the first substrate of the display device according to theembodiment, and a cross-sectional view taken along line C-A-B shown inthe vicinity of the central portion.

FIG. 3 is a cross-sectional view taken along line A-C shown in FIG. 2.

FIG. 4 is a schematic cross-sectional view when the first substrate SUB1and a second substrate SUB2 are attached to each other in a process formanufacturing the display device according to the embodiment.

FIG. 5 is a schematic cross-sectional view when a first substrate SUB1and a second substrate SUB2 are attached to each other in a process formanufacturing a display device according to another embodiment.

FIG. 6 is shown for explaining a state where a drop of a sealingmaterial 11 is put and a state after sealing material 11 is pressed andshaped in the process for manufacturing the display device according tothe embodiment of FIG. 5.

FIG. 7 is a schematic cross-sectional view when a first substrate SUB1and a second substrate SUB2 are attached to each other in a process formanufacturing a display device according to yet another embodiment.

FIG. 8A schematically shows a part of a cross-sectional surface when afirst substrate SUB1 and a second substrate SUB2 are attached to eachother in a process for manufacturing a display device according to yetanother embodiment.

FIG. 8B schematically shows a part of a cross-sectional surface when afirst substrate SUB1 and a second substrate SUB2 are attached to eachother in a process for manufacturing a display device according to yetanother embodiment.

FIG. 8C schematically shows a part of a cross-sectional surface when afirst substrate SUB1 and a second substrate SUB2 are attached to eachother in a process for manufacturing a display device according to yetanother embodiment.

FIG. 9 is a process explanatory diagram shown for schematicallyexplaining a process for manufacturing display device according to oneembodiment.

FIG. 10 includes a planar view and a cross-sectional view showing thevicinity of an inlet for a liquid crystal.

FIG. 11A shows the relationship between a polarizer and an accessoryplate around a through portion in a display device according to oneembodiment.

FIG. 11B shows a modification example of the embodiment of FIG. 11A.

FIG. 12 shows the external appearance of a watch device to which oneembodiment of the present invention is applied.

DETAILED DESCRIPTION

Various embodiments will be described hereinafter with reference to theaccompanying drawings.

Embodiments provide a display device and a method for manufacturing adisplay device, preventing a sealing material from unnecessarilyexpanding outward between a first substrate and a second substrate,reducing the width of a light-shielding film, and enhancing thereliability of a display area with respect to display.

In general, according to one embodiment, a display device comprises:

a first substrate comprising a first area, a second area, a third areaand a fourth area from an end portion to an inner side in a planar view;

an organic insulating film which is present in the second area and thethird area, and is not present in the fourth area;

a conductive film provided on the organic insulating film of the secondarea;

a second substrate facing the first substrate;

a sealing material which is present in the first area, the third areaand the fourth area, and is used to attach the first substrate and thesecond substrate; and

a through portion which is adjacent to an inner side of the fourth areaand penetrates the first substrate, the second substrate and the sealingmaterial.

The disclosure is merely an example, and proper changes in keeping withthe spirit of the invention, which are easily conceivable by a person ofordinary skill in the art, come within the scope of the invention as amatter of course. In addition, in some cases, in order to make thedescription clearer, the widths, thicknesses, shapes, etc., of therespective parts are illustrated schematically in the drawings, ratherthan as an accurate representation of what is implemented. However, suchschematic illustration in no way restricts the interpretation of theinvention. In addition, in the specification and drawings, structuralelements which function in the same or a similar manner to thosedescribed in connection with preceding drawings are denoted by likereference numbers, detailed description thereof being omitted unlessnecessary.

This specification uses the terms “upper”, “lower”, “outer” and “inner”to explain the relative positional relationships between a particularstructure and other structures in drawings. In a lateral view, thisspecification defines the color filter side relative the electroopticlayer side as the upper side, and defines the opposite side as the lowerside. In a planar view, this specification defines the edge side of eachsubstrate relative the center of the display area as the outer side, anddefines the opposite side as the inner side.

In this specification, the term “image display device” refers to adevice which displays an image with an electrooptic layer. Thus, theimage display device may be a display module (or a display panel)including an electrooptic layer, or may be a display device manufacturedby combining a display module and other elements (for example, abacklight, cover glass and a polarizer).

In each embodiment, the electrooptic layer could be a liquid crystallayer, an electroluminescence (EL) layer, an electrochromic (EC) layeror an electrophoresis layer on the condition that it does not raise atechnical contradiction. In this specification, each embodimentdiscloses a display device using a liquid crystal module including aliquid crystal layer as an example of an image display device. However,the present invention may be also applied to a display device using adisplay module including another electrooptic layer as described above.

At first one of embodiments is described.

FIG. 1A is a planar view schematically showing the structure of a firstsubstrate SUB1 of a display device 100. FIG. 1B schematically shows thecross-sectional surface of the display device 100. The first substrateSUB1 (which may be called an array substrate) comprises, for example, aglass plate (or a transparent resin plate) as the base plate. A group ofsubpixels PX_G including a plurality of subpixels is formed in a displayarea ARE1 on a side of the glass plate. As shown in FIG. 1B, the firstsubstrate SUB1 is integrated with a second substrate SUB2 by sealingmaterials 10 and 11. A liquid crystal is interposed between the firstsubstrate SUB1 and the second substrate SUB2 to form a liquid crystallayer LQ. FIG. 1B schematically shows, on the liquid crystal layer LQside of the first substrate SUB1, a semiconductor layer 21 structuring agroup of subpixels, a pixel electrode layer 22 forming a pixelelectrode, and the layer of an alignment film 58 facing the liquidcrystal layer LQ and defining the direction of alignment of the liquidcrystal. FIG. 1B also schematically shows a color filter layer COLF, acommon electrode COM, and the layer of an alignment film 59 facing theliquid crystal layer and defining the direction of alignment of theliquid crystal. The common electrode COM, the color filter layer COLFand the layer of alignment film 59 are formed on the second substrateSUB2 in this order from the glass plate side toward the liquid crystallayer LQ.

In FIG. 1A, the display device 100 is circular as seen in plan view (inother words, when viewed perpendicularly to the substrate surface).However, the display device 100 may be shaped in various ways. Forexample, the display device 100 may be rectangular, triangular orpolygonal. The present embodiment is a display device integrated with adevice having the axis of rotation, for example, a watch. Since thepresent embodiment is applied to a wearable device which is circular,the first substrate SUB1 and the second substrate SUB2 are circular asseen in plan view. In the example of FIG. 1A and FIG. 1B, sealingmaterials 10 and 11 have a circular ring shape as seen in plan view.

In FIG. 1A and FIG. 1B explained above and FIG. 2 and FIG. 3 explainedbelow, a through portion HOL is formed in a fifth area ARE5 as thecentral area of each substrate. As described later, the through portionHOL is formed after the first substrate SUB1 and the second substrateSUB2 are attached to each other.

The display device 100 is explained with enlarged views of the vicinityof the through portion HOL. See FIG. 2 and FIG. 3. As shown in FIG. 2and FIG. 3, in a planar view, the liquid crystal layer LQ side of thefirst substrate SUB1 comprises the first area ARE1, which is the borderarea shown in FIG. 1A, a second area ARE2, a third area ARE3, a fourtharea ARE4 and the fifth area ARE5 from the end portion (the outercircumferential edge) to the inner side (the inner circumferentialside). The through portion HOL (see FIG. 2) is provided in the fiftharea ARE5 such that the bearing of shafts of each hand pass through thethrough portion HOL.

The second area ARE2 is provided from the outer circumferential side tothe inner circumferential side. A display area is set in the second areaARE2. As shown in FIG. 3, a drive switching element DSW for applyingdrive potential to a pixel electrode 57 is formed on a glass plate 31 inthe display area by using a semiconductor channel 51. In the presentembodiment, a reflective display system (in other words, a system forreflecting outside light on the pixel electrode and outputting the lightto the second substrate SUB2 side) is assumed. Thus, the pixel electrodeis formed of, for example, silver. The drive switching element DSWcomprises the semiconductor channel 51, a gate electrode 52, a sourceelectrode 53 and a drain electrode 54. The semiconductor channel 51comprises a channel area at the central position facing the gateelectrode 52. The source electrode 53 is connected to a source area onone side of the channel area. The drain electrode 54 is connected to adrain area on the other side of the channel area. An insulating layer 41provided between the gate electrode 52 and the semiconductor channel 51is a first insulating layer which covers the layer of the semiconductorchannel 51. An insulating layer 42 is a second insulating layer whichcovers the layer of the gate electrode 52. The first insulating layer 41and the second insulating layer 42 extend to the vicinity of the innercircumferential end portion of the second area ARE2 as an insulatinglayer 23 shown in FIG. 2.

FIG. 3 shows only one drive switching element DSW as a representative ofthe drive switching elements DSW. However, in the actual device, aplurality of drive switching elements DSW corresponding to a pluralityof subpixels are arrayed in a two-dimensional manner inside the firstsubstrate SUB1. In the present embodiment, a display system in which amemory element is incorporated into a pixel circuit (in other words, amemory-in-pixel (MIP) display system) is employed. Thus, a memoryelement for retaining data 1 or 0 is provided so as to correspond toeach subpixel. Although not shown in the drawings, for example, aswitching element for structuring the memory element and a writeswitching element for writing data from a data line to the memory areprovided.

The source electrode 53 and the drain electrode 54 are formed of, forexample, metal such as aluminum. The gate electrode 52 is connected to ascanning signal line (not shown) formed on the first insulating layer41. The source electrode 53 is connected to a video signal line (notshown) formed on the second insulating layer 42.

An organic insulating film 61 is formed on the semiconductor layer 21.The organic insulating film 61 is formed at least in the second areaARE2. The organic insulating film 61 serves to planarize the asperitiesor unevenness of the semiconductor layer 21. Thus, the organicinsulating film 61 may be called a planarization film 61. The innercircumferential side of the planarization film 61 covers the innercircumferential edge of the insulating layer 23 (see FIG. 2(b) and FIG.3).

On the planarization film 61, the pixel electrode 57 is provided so asto correspond to the drive switching element DSW. The pixel electrode 57and the drain electrode 54 of the drive switching element DSW areconnected to each other by metal formed in a contact hole, for example,indium tin oxide (ITO; connective metal) 56 having transparency. Thecontact hole is formed in the planarization film 61.

In many cases, the subpixels on the innermost circumferential side ofthe second area ARE2 are structured as dummy subpixels. Dummy pixels arepixels which overlap a light-shielding film and do not contribute todisplay. When the subpixels are dummy subpixels, the drive switchingelements DSW are maintained so as to be always in an off-state. Thus,the actual driving is not performed. The ITO (connective metal) 56structuring a part of each dummy subpixel is formed so as to extend inthe third area ARE3 or a part of the fourth area ARE4 after theplanarization film 61 is formed. Thus, the ITO 56 covers theplanarization film 61 (see FIG. 3).

Further, alignment film 58 is formed over the entire surfaces of the ITO56 and the pixel electrode 57. Alignment film 58 may be formed in therange of the second area ARE2.

In the above display device, alignment film 58 is provided inside theinner circumferential (central) sealing material 11. The ITO 56 isprovided under alignment film 58. In the manufacturing process,alignment film 58 is applied onto the ITO, which is metal oxide. Sincealignment film 58 has a good affinity for the ITO 56, the applicationprocess is easy. Moreover, the adhesiveness to the substrate and theorganic insulating film is improved by providing the ITO 56. In thisway, it is possible to prevent moisture intrusion from outside.

The first substrate SUB′ is attached to the second substrate SUB2. Inthis case, as shown in FIG. 1A, sealing material 10 is provided in thefirst area ARE1 of the first substrate SUB1. In the manufacturingprocess, sealing material 10 is extruded in a circular pattern from adevice for applying a sealing material. In this way, sealing material 10is applied. A drop of sealing material 11 is put in the fifth area ARE5of the first substrate SUB1, in other words, where the through portionHOL is to be formed. The dot drop position is preferably the centralposition of the fifth area ARE5. The amount of sealing material 11 atthis time is appropriately set in consideration of the range ofextension of the sealing material in the outer circumferential directionwhen the first substrate SUB1 and the second substrate SUB2 are pressedagainst each other. Thus, the sealing material does not excessivelyextend in the outer circumferential direction.

FIG. 4 schematically shows a cross-sectional surface when the firstsubstrate SUB1 and the second substrate SUB2 are attached to each otherin the manufacturing process. FIG. 4 shows glass plate 31 and theplanarization film 61 on the first substrate SUB1 side. FIG. 4 shows aglass plate 81, the color filter layer COLF and the layer of alight-shielding film BM on the second substrate SUB2 side. In thefigure, the light-shielding film BM is provided on the liquid crystallayer LQ side, and the color filter layer COLF is provided on the glassplate 81 side. However, their positions may be replaced with each other.As seen in plan view, the light-shielding film BM extends at least inthe third area ARE3, the fourth area ARE4 and the fifth area ARE5. Inthe figure, the outer circumferential portion of the light-shieldingfilm BM further extends in a part of the second area ARE2. However, thisextended portion may be removed.

The light-shielding film BM is formed in the fifth area ARE5 (where thethrough portion HOL based on a z-axis is to be formed) and the vicinityof the fifth area ARE5. After the display device is manufactured, thelight-shielding film BM is allowed to effectively block light leakingout from the vicinity of the through portion HOL to the second substrateSUB2 side. If the light-shielding film BM is not provided, unnecessarylight reflected on the first substrate SUB1 side may leak out from thevicinity of the through portion HOL. In a planar view, the end portionof the light-shielding film BM may be provided in the same position asthe end portion of the first substrate SUB1, or may be provided on theinner side in comparison with the position of the end portion of thefirst substrate SUB1.

A drop of sealing material 11 is put in the fifth area ARE5. This dotsealing material 11 is extended by pressing the second substrate SUB2against the first substrate SUB1. In this way, sealing material 11 shownin FIG. 4 is formed. Sealing material 11 is cured by ultraviolet rays,etc. The space between the first substrate SUB1 and the second substrateSUB2 is filled with sealing material 11 in the third area ARE3, thefourth area ARE4 and the fifth area ARE5.

In FIG. 4, a polarizer 91 and an accessory plate 92 are shown by dashedlines since they are attached after the formation of the through portionHOL as described later. For the same reason, the polarizer 91 and theaccessory plate 92 are shown by dashed lines in FIG. 5 and FIG. 7explained later.

In the completed device, the polarizer 91 is attached to the externalsurface of glass plate 81 of the second substrate SUB2 (in other words,a side opposite to the liquid crystal layer). Moreover, the accessoryplate 92 is attached to the upper surface the polarizer 91.

Around the fifth area ARE5, the inner circumferential edge of theaccessory plate 92 is closer to the fifth area ARE5 (through portionHOL) than the inner circumferential edge of the polarizer 91. In thecompleted display device, the liquid crystal layer LQ is providedbetween the second substrate SUB2 and the first substrate SUB1. Thepolarizer 91 is provided on a side of the second substrate SUB2 so as tobe opposite to the liquid crystal layer LQ. The accessory plate 92 isprovided on the upper surface of the polarizer 91.

The radius of the inner circumferential edge of the polarizer 91 is setso as to be greater than that of the through portion HOL to preventdegradation of the polarizer 91 when the through portion HOL is formed.However, the radius of the inner circumferential edge of the accessoryplate 92 is set so as to be less than that of the inner circumferentialedge of the polarizer 91 such that the inner circumferential edge of theaccessory plate 92 is closer to the through portion HOL than the innercircumferential edge of the polarizer 91.

This structure prevents the exposure of the light-shielding film BM onthe inner circumferential side to outside, using the accessory plate 92.When the light-shielding film BM is provided on the inner side incomparison with the polarizer 91, the light-shielding film BM may beexposed to outside through the polarizer 91. However, the exposure ofthe light-shielding film BM to outside is prevented by the abovestructure. The accessory plate 92 covers and protects the end portion ofthe polarizer 91. At the same time, the accessory plate 92 prevents theexposure of the through portion HOL to outside. The accessory plate 92may be used to secure the position of an insertion member which passesthrough the through portion HOL, such as a pin. The accessory plate 92may be formed of a resin material or a metal material.

After the composition in the above manner, an opening process is appliedto the fifth area ARE5 (a hole-making portion) by, for example, a laser,to form the through portion HOL based on the z-axis as the central axis.At this time, the intermediate composite component of the firstsubstrate SUB1 and the second substrate SUB2 is filled with sealingmaterial 11 in and around the fifth area ARE5. Thus, the strength of theintermediate composite component is enhanced. As a result, a hole-makingprocess can be applied without twisting the intermediate compositecomponent. In this way, the hole-making process can be safely carriedout. In addition, the accuracy of the position or shape of the throughportion HOL can be high. The through portion HOL is formed from thestate where the fifth area ARE5 is filled with the sealing material asdescribed above. Therefore, when the through portion HOL whichpenetrates the first substrate SUB1, sealing material 11 and the secondsubstrate SUB2 is formed, the inner surface of the through portion HOLis continuous in the axial direction of the through portion on the sameplane. Thus, the inner surface is continuous without asperities.

FIG. 5 shows another embodiment. The embodiment of FIG. 5 is differentfrom that of FIG. 4 in respect that a ring-shaped groove (which may bereferred to as a slit pattern) 61 g is formed on the upper surface of aplanarization film 61 in a third area ARE3. The other structures are thesame as those of the embodiment of FIG. 4, detailed description thereofbeing omitted.

The cross-sectional surface of the groove 61 g is V-shaped. However, thecross-sectional surface of the groove 61 g may be rectangular orU-shaped, and is not limited to a particular shape. When a sealingmaterial 11 is excessively applied, the groove 61 g functions as abuffer or stopper which absorbs the redundant sealing material 11. Inthe manufacturing process, an appropriate amount of sealing material 11is preferably applied in drops to the central position of a fifth areaARE5 (on a z-axis). However, the amount or position of the applicationis not always accurate because of various conditions such as thetemperature and the viscosity of the sealing material. When a firstsubstrate SUB1 and a second substrate SUB2 are attached to each otherwith an excessive amount of sealing material 11, sealing material 11 mayextend to the outer circumferential side beyond the third area ARE3designed as the limit. To solve this problem, the present embodiment isdesigned such that the redundant sealing material 11 is absorbed by thegroove 61 g.

FIG. 6(a) shows a state 11-M where a drop of sealing material 11 is putin the fifth area ARE5 and is not pressed yet. FIG. 6(b) shows onlysealing material 11 after sealing material 11 is pressed and shaped.

The shaped sealing material 11 integrally comprises an outercircumferential portion 11 a located in the third area ARE3, anintrusion portion 11 b located in the groove 61 g, and a central portion11 c located in a fourth area ARE4 and the fifth area ARE5 where theplanarization film 61 is not present. Because of this structure, when adrop of sealing material 11 is put in the fifth area ARE5, it ispossible to relax the allowable range of the accuracy of the amount ofsealing material 11, the application position, the environmentaltemperature and the viscosity of the sealing material. Thus, themanufacturing process can be simplified.

FIG. 7 shows yet another embodiment. The embodiment of FIG. 7 isdifferent from that of FIG. 4 in respect that the thickness of aplanarization film 61 is gradually reduced toward the innermostcircumference in a third area ARE3. Thus, the planarization film 61located in the third area ARE3 comprises an inclined surface 61-S. Theother structures are the same as those of the embodiment of FIG. 4,detailed description thereof being omitted.

In this structure, the inclined surface 61-S is formed in theplanarization film 61 around a fourth area ARE4. Thus, even when theamount of a sealing material 11 is excessive, sealing material 11 hasdifficulty in going beyond the third area ARE3. Furthermore, thestrength is enhanced since sealing material 11 is thick. This embodimentis effective when the applied dot sealing material 11-M is off thecentral position of a fifth area ARE5 in the manufacturing process.Specifically, when the substrates are attached to each other, and thesealing material is pressed, the inclined surface 61-S of theplanarization film 61 functions to transfer the sealing material from anexcessive portion to a less portion. As a result, the sealing materialcan be extended equally based on the central position.

FIG. 8A, FIG. 8B and FIG. 8C show other modification examples of abuffer or stopper formed in a planarization film 61. In the example ofFIG. 8A, a ring-shaped groove 61 d is formed away from the centralcircumferential edge of the planarization film 61. In the example ofFIG. 8B, a step 61 e is formed in the central circumferential edge ofthe planarization film 61 (in other words, in the edge around a fourtharea ERA4). The height (thickness) of the step 61 e is preferably, forexample, thirty to eighty percent of that of the highest portion of theplanarization film 61. In the example of FIG. 8C, a depression 61 f isformed where the planarization film 61 enters a third area ARE3. Theother structures are the same as those of the above embodiments,detailed description thereof being omitted. In the embodiment of FIG.8C, the depression 61 f can prevent a sealing material 11 from expandingto a second area ARE2.

In a manner similar to that of FIG. 3, the planarization film 61 of FIG.4 to FIG. 8A, FIG. 8B and FIG. 8C may be covered by a conductive film(ITO). An alignment film may be formed on the conductive film.

FIG. 9 is a process explanatory diagram schematically showing a processfor manufacturing the display device of each of the above embodiments.The semiconductor layer 21 is formed on the first substrate SUB1(process PS1). The process so far may be called the preparation processof the first substrate SUB1. Subsequently, an organic film(planarization film) is formed (process PS2). To form the planarizationfilm, the process explained in FIG. 4, FIG. 5, FIG. 7 or FIG. 8A to FIG.8C is selected.

After the planarization film is formed, ITO and a pixel electrode areformed (process PS3). Subsequently, an alignment film is formed (processPS4). After the alignment film is formed, a sealing material is applied.On the outer circumferential side of the substrate, the sealing materialis applied in a circular pattern. In the fifth area ARE5, a drop ofsealing material is put. Subsequently, the first substrate is attachedto the second substrate (processes PS5 and PS6). When the base plates ofthe first and second substrates are glass plates, chemical etching isapplied with hydrofluoric acid to the glass plates such that the glassplates are thin (process PS7). Subsequently, a through portion HOL forattaching hands is formed using a laser (process PS8). As the laser, forexample, a pulsed carbon dioxide laser is used. However, the laser isnot limited to this example.

A liquid crystal is injected through an inlet provided in a part of thesealing material. After the injection, the inlet is closed (processPS9). A polarizer is attached to the external side of the secondsubstrate SUB2. Subsequently, an accessory plate is attached to theupper surface of the polarizer (process SP10). By the above procedure,the trace of the inlet remains in the display device after the liquidcrystal is encapsulated. For example, a sealant remains after the inletis closed.

In the process for manufacturing the second substrate SUB2, thepolarizer 91 is provided on a side of the second substrate SUB2 so as tobe opposite to the first substrate SUB1. Further, the accessory plate 92is provided on the upper surface of the polarizer 91. Around the fiftharea ARE5, in other words, around the through portion HOL of thecompleted device, the radius of the inner circumferential edge of thepolarizer 91 is greater than that of the inner circumferential edge ofthe accessory plate 92.

FIG. 10(a) is a planar view showing an inlet 70 formed to inject aliquid crystal. FIG. 10(b) is a cross-sectional view taken along lineX-X′ after the inlet 70 is sealed by sealant 10A. When the firstsubstrate SUB1 is attached to the second substrate SUB2, the inlet 70 isformed in a part of sealing material 10. In the inlet 70, aplanarization film 82 formed on glass plate 81 of the second substrateSUB2 faces the planarization film 61 formed on glass plate 31 of thefirst substrate SUB1. Spacers 83 a, 83 b and 83 c are provided on theplanarization film 82 of the second substrate SUB2 to maintain thestrength. The inlet 70 is sealed by the sealant 10A after the liquidcrystal is injected.

FIG. 11A shows the positional relationships between the members formedon glass plate 81 of the second substrate SUB2 and the members formed onthe first substrate SUB1 around the through portion HOL. Thelight-shielding film BM is formed on the liquid crystal layer LQ side ofglass plate 81. The polarizer 91 is attached to the external side ofglass plate 81 (in other words, to the side opposite to the liquidcrystal layer). Moreover, the accessory plate 92 is attached to theupper surface of the polarizer 91.

As seen in plan view, the light-shielding film BM near the throughportion HOL overlaps at least the second area and the third area. Thelight-shielding film BM may be provided in a part of the first area, thesecond area, the third area and a part of the fourth area. Near thethrough portion HOL, the inner circumferential edge of the accessoryplate 92 is closer to the through portion HOL than the innercircumferential edge of the polarizer 91. The liquid crystal layer LQ islocated between the first substrate SUB1 and the second substrate SUB2.The polarizer 91 is provided on a side of the second substrate SUB2 soas to be opposite to the liquid crystal layer LQ. Moreover, theaccessory plate 92 is provided on the upper surface of the polarizer 91.Around the through portion HOL, the radius of the inner circumferentialedge of the polarizer 91 is greater than that of the innercircumferential edge of the accessory plate 92. This structure preventsthe exposure of the light-shielding film BM on the inner circumferentialside to outside, using the accessory plate 92. When the polarizer 91extends to the inner circumferential side, the light-shielding film BMis exposed to outside through the polarizer 91. However, the exposure ofthe light-shielding film BM to outside is prevented by the abovestructure.

FIG. 11B is a modification example of the structure shown in FIG. 11A.In the embodiment shown in FIG. 11A, the accessory plate 92 is attachedto the upper surface of the polarizer 91. Apart from this example, awasher type accessory plate 92 a may be attached. This type of accessoryplate 92 a can also exhibit a function for retaining the position of theaxis of the through portion HOL and an aesthetic appearance designingfunction which prevents the exposure of the light-shielding film BM tooutside.

FIG. 12 shows an example of the external appearance of a watch device(wearable device) 300 to which the present invention is applied. Acircular dial 130 is retained by a ring-shaped outer casing 140. Asexplained in the above embodiments, the dial 130 comprises the firstsubstrate SUB1, the second substrate SUB2, the liquid crystal layer LQ,etc., and is capable of functioning as a display device. The shaft of along hand 131 and the shaft of a short hand 132 pass through the throughportion HOL. The long hand 131 and the short hand 132 rotating based onthe axes along the upper surface of the dial are attached to the shaftof the long hand and the shaft of the short hand, respectively. Theshaft of the long hand and the shaft of the short hand are rotated by aclock motor provided inside the watch device 300.

In the display device, its display function is effectively used. Forexample, the display device is capable of displaying the current date135 and the plans for the date 136. For example, a memory chip ismounted to display a schedule, a date and a message. Data is input tothe memory chip from, for example, a personal computer. The watch device300 may have a wireless communication function, receive a specific radiowave from outside and load the data of the schedule for meetings intothe memory chip.

While certain preferred embodiments have been described, theseembodiments have been presented by way of example only, and are notintended to limit the scope of the invention. Various changes may bemade without departing from the spirit of the invention. Each embodimentmay be applied to a display device for a vehicle speed meter in which athrough portion such as a circular hole is provided in a display area,as well as a display device for a watch. Furthermore, each embodimentmay be applied to a smart phone having a display area which is formedthrough portion to avoid a position corresponding to a camera. Moreover,each embodiment may be applied to a display device for a gauge or meterfor various vehicles such as an airplane, a boat, a ship and a railwayvehicle. Proper changes in keeping with the spirit of the invention comewithin the technical scope of the invention as a matter of course.

What is claimed is:
 1. A display device comprising: a first substratecomprising a first area, a second area, a third area and a fourth areafrom an end portion to an inner side in a planar view; an organicinsulating film which is present in the second area and the third area,and is not present in the fourth area; a conductive film which ispresent at least on the organic insulating film of the second area; asecond substrate facing the first substrate; a sealing material which ispresent in the first area, the third area and the fourth area, and isused to attach the first substrate and the second substrate; and athrough portion which is adjacent to an inner side of the fourth area,and penetrates the first substrate, the second substrate and the sealingmaterial.
 2. The device of claim 1, wherein a thickness of the organicinsulating film changes in a portion corresponding to the third area. 3.The device of claim 1, wherein the organic insulating film comprises aslit in a portion corresponding to the third area, and the slit isfilled with the sealing material.
 4. The device of claim 1, wherein athickness of the organic insulating film in a portion corresponding tothe third area is gradually decreased toward the fourth area.
 5. Thedevice of claim 1, wherein the conductive film covers an end portion ofthe organic insulating film.
 6. The device of claim 1, wherein an innersurface forming the through portion penetrating the first substrate, thesealing material and the second substrate is continuous along an axis ofthe through portion.
 7. The device of claim 1, wherein a liquid crystallayer is provided between the first substrate and the second substrate,a polarizer is provided on a surface of the second substrate opposite toa surface of the second substrate facing a liquid crystal layer, anaccessory plate is provided on an upper surface of the polarizer, and aradius of an inner circumferential edge of the polarizer is greater thana radius of an inner circumferential edge of the accessory plate aroundthe through portion.
 8. The device of claim 2, wherein a liquid crystallayer is provided between the first substrate and the second substrate,a polarizer is provided on a surface of the second substrate opposite toa surface of the second substrate facing a liquid crystal layer, anaccessory plate is provided on an upper surface of the polarizer, and aradius of an inner circumferential edge of the polarizer is greater thana radius of an inner circumferential edge of the accessory plate aroundthe through portion.
 9. The device of claim 3, wherein a liquid crystallayer is provided between the first substrate and the second substrate,a polarizer is provided on a surface of the second substrate opposite toa surface of the second substrate facing a liquid crystal layer, anaccessory plate is provided on an upper surface of the polarizer, and aradius of an inner circumferential edge of the polarizer is greater thana radius of an inner circumferential edge of the accessory plate aroundthe through portion.
 10. The device of claim 4, wherein a liquid crystallayer is provided between the first substrate and the second substrate,a polarizer is provided on a surface of the second substrate opposite toa surface of the second substrate facing a liquid crystal layer, anaccessory plate is provided on an upper surface of the polarizer, and aradius of an inner circumferential edge of the polarizer is greater thana radius of an inner circumferential edge of the accessory plate aroundthe through portion.
 11. The device of claim 5, wherein a liquid crystallayer is provided between the first substrate and the second substrate,a polarizer is provided on a surface of the second substrate opposite toa surface of the second substrate facing a liquid crystal layer, anaccessory plate is provided on an upper surface of the polarizer, and aradius of an inner circumferential edge of the polarizer is greater thana radius of an inner circumferential edge of the accessory plate aroundthe through portion.
 12. The device of claim 6, wherein a liquid crystallayer is provided between the first substrate and the second substrate,a polarizer is provided on a side of the second substrate so as to beopposite to the liquid crystal layer, an accessory plate is provided onan upper surface of the polarizer, and a radius of an innercircumferential edge of the polarizer is greater than a radius of aninner circumferential edge of the accessory plate around the throughportion.
 13. The device of claim 1, further comprising a light-shieldingfilm which is formed on a liquid crystal layer side of the secondsubstrate, surrounds the through portion and at least extends to thethird area in a planar view.
 14. The device of claim 2, furthercomprising a light-shielding film which is formed on a liquid crystallayer side of the second substrate, surrounds the through portion and atleast extends to the third area in a planar view.
 15. A method formanufacturing a display device, the method comprising: a preparationprocess for preparing a first substrate, the first substrate comprisinga first area, a second area, a third area, a fourth area and a fiftharea adjacent to the fourth area from an end portion to an inner side ina planar view; an organic film formation process for forming an organicinsulating film in the second area and the third area of the firstsubstrate such that the organic insulating film is formed neither in thefourth area nor in the fifth area; a conductive film formation processfor forming a conductive film continuous on the organic insulating filmof the second area and the organic insulating film of the third area; anattachment process for applying a first sealing material to the firstarea of the first substrate, putting a drop of a second sealing materialin the fifth area, and attaching a second substrate and the firstsubstrate comprising the organic insulating film and the conductive filmby the first and second sealing materials; and a penetration process forforming a through portion which penetrates the first substrate and thesecond substrate in the fifth area.
 16. The method of claim 15, whereinin the penetration process, the through portion is formed by irradiatingthe fifth area with laser light.
 17. The method of claim 15, wherein inthe organic film formation process, the organic insulating film isformed such that its thickness changes in a portion corresponding to thethird area.
 18. The method of claim 15, wherein in the organic filmformation process, the organic insulating film is formed so as to have aslit pattern in a portion corresponding to the third area.
 19. Themethod of claim 15, wherein in a process for manufacturing the secondsubstrate, a polarizer is provided on a side of the second substrate soas to be opposite to the first substrate, and an accessory plate isprovided on a side of the polarizer so as to be opposite to the secondsubstrate, and the polarizer and the accessory plate are provided suchthat a radius of an inner circumferential edge of the polarizer isgreater than a radius of an inner circumferential edge of the accessoryplate around the through portion.
 20. The method of claim 15, furthercomprising a process for attaching a polarizer to a side of the secondsubstrate so as to be opposite to the liquid crystal layer after thepenetration process, and attaching an accessory plate to a side of thepolarizer so as to be opposite to the second substrate.